I know it's kind of late to chime in here, but, I feel I need to share my experience with you. We got our first basenji in March '96 and our 2nd in December of that same year, brother and sister from year apart litters. They could not have been more different. Our female was an angel, an occasional basenji high jinx, but her brother, imp all the way. He was a biter from the get go. Like you, we tried everything. What finally worked or us, immediately stop play, stand up, fold arms, out of reach, and turn our backs from the puppy. He quickly got the message, that biting of any kind would not be tolerated. I really need to caution you here, any kind of biting, even in play, should not be allowed, as this most likely will become an issue for you in the future, especially if you plan on having children in your home. He will think that it's okay to put his teeth on/into your skin. I ought to know as our Bolt, although very much loved in his original home, after 6 years, had to be rehomed due to biting issues. We are his 4th home. Not everyone can cope with an adult biting dog. It's best to deal with it now.
They are very smart dogs. I say they are more like a 2 year old in a dog suit. BUT, what works for one does not mean it will work for another, and sometimes, it will only works once. They can be very challenging, but the reward, that, that is limitless, and why so many of us have them. If you ask most of our relatives, they simply think we are nuts for having 'crazy' dogs!